Odd sound issue with only Netflix dvd's

Hello and thanks in advance for any suggestions with this issue.
OK my audio is on my mobo and currently I run an audio optical out to a DA converter and into my stereo which works beyond great. All my dvd's and blue rays play perfectly so here's the challenge. Recent signed up for Netflix and now with the 1st and 2nd dvd when their inserted into the optical drive it plays perfect but has no audio. I remove the disk from the optical drive bay and it returns sometimes or if I make another audio device default then switch back to the Realtek Digital Output (Optical). If I play this on my laptop or my other desktop rig it plays with sound just as it should. Odd very odd !

All realtek drivers are up to date.

Yeah I'm dumb founded as well !

Hi,
Are these recent movies and the rental versions Neftlix and other providers have or just older DVD's? I am positive the newer rental movies on DVD / Blu Ray are copy protected with the latest protection and this may be the issue. The audio driver sees a complicated audio path and you maybe doing something that is not allowed as they think you are trying to make some kind of a copy. I'll wager analog audio works fine?
Tony

Tony,
These are recent dvd movies. I think you could be on to something as if seeing the digital output makes the dvd go silent or actually tells the rig to lock out the optical output? I place the dvd in my old rig running analog and all is fine.